DELIVER(8) MAINTENANCE COMMANDS DELIVER(8)
NAME
deliver - deliver local mail
SYNOPSIS
deliver [ options ] address ...
DESCRIPTION
The deliver program collects a mail message from the stan-
dard input and delivers it. It is intended to take over the
delivery of all local mail, a job usually handled by
/bin/mail (System V), /usr/lib/sendmail (BSD), or
/usr/lib/mail/mail.local (Xenix).
deliver introduces flexibility in the handling of local mail
delivery. All files used to control deliver are shell
scripts. Thus anything that can be called by a shell script
can be used to control mail delivery.
OPTIONS
-b Interpret all arguments as mailbox filenames instead of
addresses. Note that the user running deliver must
have write permissions on the given mailbox files. He
may also need write permissions on their parent direc-
tories, depending on the existence of the mailbox file
and the local locking protocol.
-n Interpret arguments as addresses, but do not run any
delivery files; simply deliver the message to the
mailbox(es) of the given user(s). This option is most
useful when deliver is executed recursively, since it
prevents further recursion.
-A Print resolved addresses; do not deliver the message.
Note that deliver still collects a message from the
standard input, since delivery files may do different
things depending on message content. For simple test-
ing, redirect standard input from /dev/null.
-d Be verbose; don't deliver to any mailboxes or catch any
signals.
-v Be verbose, but still deliver.
-t Do not remove temporary files before exiting.
-r sender
Put sender on the generated From_ line. Default is to
use the address on the From_ line in the input, or else
the name corresponding to the real uid, or else "unk-
nown".
-h hostname
Set the host name. The default is configuration depen-
dent.
-s system delivery file
Specify an alternate system delivery file. The default
is /var/deliver/deliver.sys. For security reasons, this
option disables setuid privileges.
-p post-user delivery file
Specify an alternate post-user delivery file. The
default is /var/deliver/deliver.post. For security rea-
sons, this option disables setuid privileges.
-e error delivery file
Specify an alternate error delivery file. The default
is /var/deliver/deliver.err. For security reasons, this
option disables setuid privileges.
-u user delivery file
Specify an alternate user delivery file. The default
is .deliver (in each user's home directory). For secu-
rity reasons, this option disables setuid privileges.
All command line options are put into environment variables,
examined by deliver on startup; thus all flags are pro-
pagated when deliver is invoked recursively.
ENVIRONMENT
For mail systems based on smail 2.x, the LMAIL (local
mailer) macro can be changed to call deliver. For mail sys-
tems based on smail 3.x or sendmail, a similar arrangement
may be made; or individual users can invoke deliver by men-
tioning it in their .forward files.
For Xenix systems, deliver may be used as a direct replace-
ment for /usr/lib/mail/mail.local.
For stock Unix systems, it may be possible to make
/bin/rmail a link to deliver; however, this configuration
has not been tested and is not recommended. Any postmaster
motivated enough to install deliver, and who wants something
better than the standard /bin/rmail, should install smail.
OPERATION
By default, deliver deposits mail in the system mailbox for
the named user(s). Also, as a necessity for use with smail
2.x, deliver also understands UUCP-style bang addresses well
enough to forward the message correctly, using uux.
However, this basic behavior only scratches the surface: the
usefulness of deliver derives from its flexibility; its
behavior can be made to depend on the recipient(s), content
or any other aspect of mail messages.
When deliver starts execution, it interprets its arguments
in one of three ways. If the -b (mailbox) option was speci-
fied, then all arguments are interpreted as mailbox path-
names. Otherwise, if a system delivery file exists and the
-n (no delivery files) option was not specified, deliver
executes the system delivery file with all of deliver's
arguments as its arguments. deliver interprets the delivery
file's output as described below. This procedure gives the
postmaster control over delivery to non-existent hosts and
users. If the -n option is specified or if there is no sys-
tem delivery file, deliver interprets all its arguments as
mail addresses.
After possibly executing the system delivery file, deliver
looks in its list of destinations for valid user names
without explicitly named mailboxes. If any of these users
have user delivery files in their home directories, and if
the -n option was not specified, deliver executes each
user's delivery file with the name of the given user as its
only argument.
After executing any user delivery files, deliver looks in
its list of destinations for simple user names and UUCP
addresses. If any are found, if the post-user delivery file
exists, and if the -n option was not specified, deliver exe-
cutes the post-user delivery file with these addresses as
its arguments.
After executing the post-user delivery file (if any),
deliver attempts delivery to all requested destinations.
After delivery to all destinations, deliver looks in its
list of destinations for failures of any kind. If any
failed destinations are found, and if the -n option was not
specified, deliver executes the error delivery file with the
complete list of failed addresses as its arguments. If the
error delivery file generates any destinations, deliver
attempts delivery to them. However, if such delivery fails,
deliver will not execute the error delivery file more than
once.
DELIVERY FILES
Delivery files are shell scripts. They are executed by
deliver to control delivery to users. Note that delivery
files do not control delivery to explicitly named mailboxes.
(See the -b option.)
The default shell used to execute delivery files is
configuration-dependant. Typically it is the Bourne shell
(/bin/sh). However, you can make deliver execute a given
delivery file with a different shell by putting a Berkeley-
style "#!" line at the top of the delivery file. For exam-
ple, if the first line of a delivery file is "#!/bin/perl",
then deliver will execute /bin/perl instead of /bin/sh, but
only for that one delivery file.
On each system the postmaster may create a system delivery
file to controls delivery of all messages. The system
delivery file, if it exists, is executed with the name(s)
specified on the deliver command line as its arguments.
The postmaster may also create a post-user delivery file
which is executed after any user delivery files, but before
delivery of the message to any mailboxes. This file is par-
ticularly useful for implementing system-wide aliases, since
it can deal with addresses generated by user delivery files,
whereas the system delivery file cannot.
Each user may create a user delivery file in his home direc-
tory. User delivery files are always executed with exactly
one argument: the name of the user in whose home directory
the file is found.
Finally, the postmaster may create an error delivery file.
After deliver has attempted delivery to all requested desti-
nations, and if delivery to one or more of those destina-
tions failed, deliver executes the error delivery file with
the list of failed adresses as its arguments. Note that
failed addresses may contain whitespace, shell metacharac-
ters or other strangeness--be careful!
Recursive execution of deliver is useful, especially with
the -b (mailbox) and -n (no delivery files) flags. For
example, a user may wish to transform a message body before
it is stored in a mailbox. This may be done with a user
delivery file and recursive execution of deliver. For exam-
ple, the following user delivery file translates all incom-
ing message bodies to lower case, and stores them in the
user's default mailbox:
(cat $HEADER; tr '[A-Z]' '[a-z]' <$BODY) | deliver -n "$1"
When deliver executes a delivery file, it sets several
environment variables, listed below. Note that these
environment variables are both set and used by deliver;
therefore, all command line options automatically propagate
when deliver is run recursively (within a delivery file).
The environment variable names set and used by deliver are:
DELPID
The process id of the running deliver process. Used by
a child deliver to determine its parent's process id.
DELLEVEL The deliver recursion level. Each time
deliver is called recursively, this value is incre-
mented. When the maximum recursion level (default:
eight) is exceeded, deliver assumes infinite recursion
and aborts. DELFLAGS The command line flags, if any,
specified on the deliver command line.
SYSDELFILE
The system delivery filename.
POSTDELFILE
The post-user delivery filename.
ERRDELFILE
The error delivery filename.
USERDELFILE
The user delivery filename, relative to the home direc-
tory of each user.
HOSTNAME
The local host name, either the real hostname or a name
specified with the -h option to deliver.
SENDER
The sender, either an address specified with -r option
to deliver, or the address given in the From_ line of
the message, or the user who invoked deliver.
HEADER
The name of the temporary file containing the message
header.
BODY The name of the temporary file containing the message
body.
deliver monitors the standard output of delivery files for
lines in four formats:
host1!host2!user
Send the message with UUCP via the given bang path.
user Append the message to the given user's default mailbox.
The location of a user's default mailbox is
configuration-dependant.
user:mailbox
Append the message to the specified mailbox in the
given user's context. If the mailbox name is not an
absolute pathname, it is interpreted relative to the
given user's home directory. For security reasons,
only the superuser may request delivery to a specific
mailbox in another user's context.
user|command
Execute the specified command in the given user's con-
text, and feed the message to its standard input. For
security reasons, only the superuser may request com-
mand execution in another user's context.
user?error message
Do not attempt delivery to the given user. Diagnostic
messages, including the bounce notice (if any), will
include the specified message. For security reasons,
only delivery files executing as the superuser may
report an error for another user.
Note that for the "user:mailbox", "user|command" and
"user?error message" forms, the user name may be omitted
(for example: "?Sorry"). If the user name is omitted, the
current user context is assumed.
UNDELIVERED MAIL
When deliver executes a delivery file, it expects a complete
list of all users (and, optionally, mailboxes) that should
receive the message. If a delivery file produces no output,
deliver saves the message in the "undelivered mail" mailbox
named "Undel.mail" in the home directory of the delivery
file's owner. (System, post-user and error delivery files
are "owned" by root.)
Sometimes a delivery file writer really does want deliver to
drop a message. For example, if a delivery file stores a
message by running "deliver -b", then there's no need for
the parent deliver to save the message again. A delivery
file can tell deliver not to save the message by outputting
the string "DROP". A delivery file's outputting "DROP" the
"undelivered mail" safety net for that delivery file. Think
of "DROP" as shorthand for: "Trust me. I know what I'm
doing." However, if the delivery file outputs any names
and/or addresses in addition to "DROP", then "DROP" has no
effect.
Note, however, that the error delivery file is an exception
to the "DROP" rule. The error delivery file never receives
valid addresses as arguments, so producing no output is con-
sidered completely normal.
SECURITY
If deliver is setuid root -- which it should be for normal
operation -- then the system delivery file is executed as
root. Be very careful about its permissions and its con-
tents! Carelessness here can easily create a security prob-
lem.
All user delivery files are executed in the context of the
user in whose home directory they reside. A user's "con-
text" includes the uid, gid, and home directory as specified
in /etc/passwd.
For security reasons, if a user's home directory is writable
to the world, deliver will ignore any delivery file that
might be found there.
For security reasons, no user can request writing a mailbox
as another user. Otherwise, any user could modify other
users' private files.
LOGGING
Deliver records its activity in two files: the "delivery
log", named /var/adm/deliver.log, and the "error log", named
/var/adm/deliver.errlog.
The deliver log is a record of activity of each deliver pro-
cess. Each delivery log entry include the users or mail-
boxes named on the command line, the users and/or mailboxes
where delivery succeeded, and those where it failed. Note
that deliver will write to the delivery log only if it
already exists.
The error log is a record of any problems encounted during
delivery. Each error log entry includes all diagnostic out-
put, a copy of the message header, and other miscellaneous
information that might prove helpful.
If deliver is performing a "dry run" -- that is, if the -d
(debug) or -A (print address) flag is specified -- it will
not write to either log file.
If you want a delivery log, you must create the delivery log
file yourself. If the delivery log file does not exist,
deliver will not create it.
If the -v (verbose) flag is specified, deliver will not
write to the error log.
LOCKING
Several preprocessor labels may be defined during compila-
tion to control the method(s) used by deliver to lock mail-
boxes. These labels are:
ML_DOTLOCK Lock on exclusive creation of the mailbox
name with ".lock" appended. (Version 7 and early BSD
mailers use this method.)
ML_DOTMLK Lock on exclusive creation of
/tmp/basename.mlk, where basename is the last component
of the mailbox pathname. (Xenix mailers use this
method.)
ML_LOCKF Exclusively lock mailbox with lockf().
ML_FCNTL Exclusively lock mailbox with fcntl().
ML_LOCKING Exclusively lock mailbox with locking().
One or both of ML_DOTLOCK and ML_DOTMLK may be specified.
At most one of ML_LOCKF, ML_FCNTL or ML_LOCKING may be
specified.
FILES
/var/deliver/deliver.sys system delivery file
/var/deliver/deliver.post post-user delivery file
/var/deliver/deliver.err error delivery file
~user/.deliver user delivery file(s)
/var/adm/deliver.log delivery log
/var/adm/deliver.errlog error log
/etc/systemid system name (Xenix only)
SUPPORT
Enhancements, enhancement requests, trouble reports, etc.,
should be mailed to  or
.
SEE ALSO
mail(1), uux(1), smail(8), sendmail(8)
Sun Release 4.1